Heater modules for warming a battery module mounted on an electric vehicle and the like are known. For example, a heater module arranged to oppose a side surface of a battery module is disclosed in JPA-2012-190690, and a heater module fixed on a lower surface of a battery module is disclosed in JPA-2008-186621.
The heater module disclosed in JPA-2012-190690 is arranged to oppose the side surface of the battery module, but is a separate body from the battery module. Therefore, there is a problem that it takes time in installing the heater unit on a vehicle or the like.
The heater module disclosed in JPA-2008-186621 can be handled integrally with the battery module and thus can be easily installed on a vehicle or the like. However, since the heater module is fixed on the lower surface of the battery module, the hearer module is not suitable for installation in a space, of which height dimension is limited.
When a heater module is fixed on a side surface of a battery module so that the heater module can be handled integrally with the battery module, it is conceived that the heater module constituted of a heat equalizing plate, a heater and a heater cover is fastened to the side surface of the battery module via a metal stay. However, in order to prevent the heat equalizing plate, on which the heater having a relatively heavy weight is attached, from falling out, a rigidity of the heater cover needs to be increased. On the other hand, if a thickness of the heater cover is increased for the purpose of increasing the rigidity of the heater cover, then an increase in size, weight and manufacturing cost is caused.